1. Field of the Invention
The present invention relates generally to an apparatus and method for molding soft contact lenses, and particularly an apparatus and method for precuring a polymerizable monomer or monomer mixture under pressure to form a soft contact lens.
2. Discussion of the Prior Art
U.S. Pat. No. 4,495,313 to Larsen, now assigned to the assignee of the present application, discloses the polymerization of a monomer to form a soft contact lens by means of ultraviolet light. In addition, this reference also teaches that an ultraviolet light catalyst can be added to the polymerization system to effect an essentially complete polymerization.
U.S. Pat. No. 5,039,459 to Kindt-Larsen et al. entitled "Method of Forming Shaped Hydrogel Articles Including Contact Lenses" teaches the polymerization of soft contact lenses wherein the monomer/diluent mixture in a transparent polystyrene mold is exposed on one side to 1.7 jewels/centimeter squared of ultraviolet radiation for ten minutes at 55.degree. C. (TL 09 lamps with peak radiation of 350 nm).
In addition to these two references, U.S. Pat. Nos. 4,565,348; 4,680,336; 4,640,489 and 5.080,839 all disclose the polymerization of a monomer with ultraviolet light to form a soft contact lens. The entire disclosure of each of these references are hereby incorporated by reference into this patent application.